Bottleneck on the superhighway

The existing telecommunications system is struggling to meet the demand for fast internet access. There is a super-fast solution, if only BT would sharpen up its act.

Analysts at Cambridge-based high-tech company Cambashi could surf the internet much quicker than they do now — if only the company could get its new go-fast line installed. Peter Thorne, director of consulting at this firm of independent consultants in the manufacturing industry says the company ordered an Asymmetrical Digital Subscriber Line (ADSL) line early this year. But so far there is no sign of this new faster internet service.

The slow roll-out of ADSL, on which BT conducted trials in East Anglia for providing video on demand as long ago as the mid 1990s, has become a cause of intense friction between BT, rival telecoms operators and the regulator, Oftel.

Rival operators accuse BT of abusing its monopoly over local exchanges and connections — ‘the local loop’ — to prevent them offering their own high-speed services. For this they need access to install equipment in BT’s exchanges, a process known as ‘unbundling’ the local loop.

Next week BT chief executive Sir Peter Bonfield appears before the House of Commons Trade and Industry select committee to defend his company.

He will face some tough questions. frustration among rivals (who will give evidence to the committee immediately before Bonfield arrives) is reaching boiling point. BT will need to come up with some sound technical arguments about why ADSL has taken so long to appear,

Lack of capacity

ADSL is designed to get to grips with the problem of a lack of capacity for transferring data in large quantities in the last stage of the telephone network — the local loop. Generally, although phone companies have installed high-capacity optical fibre lines for their trunk networks, the last few miles from local exchanges is still copper wire, which has limited capacity. Installing fibre to every household and business, however, is not a viable economic proposition.

ADSL is a way of compressing broadband data to allow it to be sent over copper wire at a fast-enough rate to be practical for uses such as fast access to the internet or intranet, access to remote local area networks (LAN), and video on demand. All these are applications where you want to receive data much more rapidly than you want to send it, hence the ‘asymmetric’ tag.

Cambashi is the sort of business that the telecoms companies have in their sights for ADSL. The prime target is the small-to-medium-sized business that wants to exchange data, and use the internet faster than it can do now with dial-up modems.As a part of its activities, Cambashi has its own ‘spider’, a search engine it calls an e-Xpert.

The e-Xpert’s job is to send out probes to websites, and then manage the flood of information that comes back. What it needs is an ‘always on’, unmetered link to the internet. Because as far as Cambashi is concerned, cutting the cost of internet services is a priority.

Experience in the US demonstrates the likely demand. Last year, US phone companies only bought sufficient hardware from the market leading supplier, Alcatel, to connect 80,000 avid surfers. This year, the total will be more like one million.

And the latest estimate suggests that the numbers of ADSL subscribers in the US will rise to 9.8 million by 2004.

What is holding things up?

The UK, though, has only 14,000 ADSL subscribers to the US’s 1.4 million. There are a number of problems: the physical installation of equipment at the consumer’s end and within exchanges; organisational issues within BT; a deliberate policy within BT to learn from US experience and solve early problems rigorously; and lack of space for new equipment in exchanges. BT’s competitors would add to this BT’s monopoly over the local loop.

First, installation. Unfortunately, installing ADSL is not simply a case of beefing up the phone exchanges and plugging a new modem into your computer. To connect to ADSL, customers need another box plugged into their phone system, plus a circuit board in the exchange to talk to this box. Unlike certain improvements in dial-up technology, ADSL needs a technician to fit the equipment. This is one reason why the take-up, and cost, of ADSL will be slower and dearer than the adoption of new dial-up modem technologies.The need for someone to install the kit — and from US experience the potentially complicated task of getting computers and modems to talk to each other — throws the onus for ADSL on to the likes of BT. The company admits that since starting to sell the service in earnest in September it has ‘experienced some difficulties’.

Second, BT’s internal organisation. Peter Thorne admits that rolling out new technology such as ADSL is ‘clearly a major project’ for BT, but adds that BT is ‘a big organisation’. That, though, could be a part of the difficulty. BT’s problem is not, it seems, so much the technology, as its own systems for processing orders and dealing with customers.

The company says that part of this is due to regulators’ requirements that it keep various parts of its own operations at arm’s length from one another, making it difficult to coordinate work that involves more than one aspect of the business.

So if the UK is to meet what should be a huge demand for ADSL — as in the US — then clearly BT has to sort out these organisational issues.

The third factor is BT’s policy. One advantage that ‘late adopters’ of ADSL have is that they can learn from the US. To exploit that experience, BT has recruited an independent consultant who knows the US scene.

Ernie Gallo, senior director of US consulting firm Telcordia Technologies, says: ‘The early implementation of consumer and small business broadband services, both cable and DSL-based, has been difficult for every operator that has tried it, regardless of country.’ BT’s strategy is to ensure that everyone learns from customers’ horror stories. The company says that it is tracking, identifying and analysing problems as they arise. Then the hope is that it can deploy improvements that apply across the system, rather than introducing ‘quick fixes’ that lead to further problems.

Rivals, though, say BT is playing for time by stalling the unbundling process to work on its ADSL product and give it a head start when competition finally does arrive.

Some satisfied customers

But it is not all bad news — and even with the slow roll out there are satisfied customers. One enthusiast is Tony Atkins, technical director for Stockport-based computer company D Kippin. Employing around 20 people, the company was one of the lucky few to get an early ADSL link from BTopenworld. ‘It’s 10 times faster than our narrow-band connection,’ says Atkins, ‘which means we can download huge files in minutes. Now the internet is more an everyday tool rather than a luxury.’

The fourth factor is installation problems in exchanges.

Exchanges are the real battleground for ADSL. They, and the copper that joins them to the nation’s fixed-phone owners, are still a part of the BT empire. This upsets many of the companies that believe that they can do a better job of bringing services such as ADSL into commercial reality.

BT says electromechanical systems may have given way to electronics, but there are still limits to how much hardware you can cram into an exchange. Equally important, electronic equipment needs cooling, which can also limit the number of circuit boards you can plug into a rack. It has drawn up a blacklist of exchanges that it says cannot be adapted.

It met its own targets of equipping 400 exchanges, covering 25% of homes and businesses, by March this year, and 619 exchanges covering 40% by October. BT’s plan now is to modify 839 exchanges, covering 50% of homes and businesses, by the end of March, 2001. Quite when they will get the service is another matter.

Last year, Fibernet Group and Norweb Telecom, which both want a share of the action, levelled the accusation that delays ‘in allowing BT’s competitors access to local telephone exchanges, will erode the commercial advantage that low-cost, high-speed multimedia services will bring to the UK’s businesses’. To them, BT’s stranglehold over ADSL hampers not just them, but also ‘’.

The broadside was a response to an Oftel paper on the unbundling of the local loop, and bringing broadband to the consumer. Companies such as Fibernet, which operates a national fibre-optic transmission network, have been pressing for wider access to the copper to the home so that other operators can provide ADSL services to customers.

Enhanced performance

In August, Fibernet announced plans to help other telecom companies and internet services providers to deliver SDSL (see box). The company’s version will, says marketing director Nigel Pitcher, ‘provide a 20% distance/performance improvement over competing DSL technologies’.

At the beginning of November, BT announced that ‘more than 14,000 users’ are now connected to various service providers ‘all using BT’s wholesale ADSL products’. The company says that it ‘now expects to ramp up end-user installations to more than three times the current rate, by next March’, so by then there could be between 70,000 and 80,000 happy surfers.

Meanwhile, in an effort to break the logjam, Oftel has given BT until February to strike an inerconnection agreement with rivals Thus and Energis. This would allow ADSL traffic to be shared between BT’s network and their own, allowing Thus and Energis to offer high speed connections by next May.

This may not be enough. Other telecoms companies are still threatening to bypass the regulator and complain directly to the Office of Fair Trading.

Explaining the many hues of DSL

Such are the flavours of Digital Subscriber Line (DSL), that they have a generic tag, xDSL. ‘Even today, several new DSL technologies are under development,’ says Jan Boström, of Ericsson Access Application Lab in Stockholm. So what does it all mean? Here’s a breakdown.


This is asymmetric DSL, the one that most domestic consumers are likely to see. That’s because their interest will be receiving video over the plain old telephone system, or POTS, as it is know to aficionados. ADSL sits happily alongside the telphone system without interfering with normal calls.

The two can co-exist because the ordinary phone system operates at signal frequencies below 4kHz. This is well below the 1MHz that a pair of twisted copper wires can carry. The various DSL technologies operate at these higher frequencies. Signals at these high frequencies are more prone to interference and noise than ordinary phone calls. So there is a limit to how far you can send signals. For ADSL to work, subscribers have to be within about 4km of the nearest telephone exchange.

HDSLHigh Bit-Rate DSL. Needs two phone lines, and achieves similar throughput to SDSL.


SDSL is symmetric, or single-line, DSL, with the same speed of data transfer to and from the subscriber. This one will appeal to businesses which want a decent throughput in both directions.


VDSL is very high-speed DSL. Here communications rates can get as high as 6.4Mbit/s download and 2Mbits/s uploads. Because it is more demanding, customers have to be nearer to an exchange, more like 1.5km. An alternative idea is to bring fibre-optic links tostreet side boxes, and to use VDSL to carry the signal on the last leg.

Some companies see VDSL as more significant than ever-faster net access. For example, optical telecoms systems manufacturer BATM believes that VDSL and ethernet protocols, the technology behind the local area networks that pervade the modern office, could connect us all to the world’s optical networks. The planet then becomes one huge global area network.

Telecoms engineers have devised various flavours of these DSLs, such as ADSL Lite and short-range and long-range VDSL. This prompts Jan Boström to worry that each generation of this technology could land the operator with the need to install new kit. Boström believes a generic modem could handle various flavours of DSL. Then, when the operator wants to upgrade a customer who has moved on to the next technology, they don’t have to send a technician out to the exchange. Instead, they could do it by sending control codes down the lines.